June 2013
CONSTRUCTION WORLD
65
products & services
THE MSA CLOSED CIRCUIT
breathing
apparatus is specifically designed for long
duration missions, and comes fully fitted
with potassium hyperoxide (KO
2
) canisters
that provide for four hours of breathing
support for emergency and rescue teams
in confined spaces.
The MSA AirElite 4h was officially in-
troduced to the South African market in
November 2012 by MSA Africa. points out
that the breathing apparatus is particularly
well suited to numerous applications, in-
cluding; mining rescue teams, firefighters,
chemical industries, refineries, military
facilities and port authorities.
KO
2
– function and reaction
Exhaled air, enriched with carbon diox-
ide (CO
2
) and moisture, is directed into
the exhalation bag by the valve control.
A blower assists the air in its passage
through the air distributor and into the two
parallel connected KO
2
canisters. Inside the
KO
2
canisters, with their maintenance free
cooling, the exhaled air is liberated of car-
bon dioxide and humidity, and is enriched
with fresh oxygen (O
2
).
Mohun highlights the fact that another
important aspect of KO
2
is that it offers
optimal O
2
surplus, due to the fact that
there is no compressed O
2
reserve, which
may cause CO
2
intoxication if the soda lime
cartridge is exhausted prematurely. She
continues: "The risk of CO
2
intoxication is
therefore entirely eliminated with the MSA
AirElite 4h."
According to Mohun, the functioning
principle of KO
2
makes bottled compressed
oxygen and additional carbon dioxide
absorbers obsolete. "If nitrogen needs to
be flushed, this occurs automatically by
the oxygen surplus. The reaction heat is
reliably absorbed by the air cooled heat
exchanger and the entirely maintenance
free water cooling
effect of the canis-
ters. Enriched with
fresh oxygen and
pleasantly cool, the
breathing air then
passes through
the par ticle
filter into the
inhalation
Revolutionary new breathing apparatus
MSA has enhanced its reputation as a global leader in the development,
manufacture and supply of sophisticated products that protect
people's health and safety, following the development of the AirElite
4h – the world's first KO
2
breathing apparatus.
of the user as its top priority. "This is
clearly evident in the fact that the MSA
AirElite 4h not only satisfies the approval
requirements of the DIN 58652-2 and
vfdb 0802 standards, but has also passed
the tough Flame EngulfmentTest for min-
ing and fire brigades, with flying colours.
The MSA AirElite 4h is also controlled by
an integrated control and display unit,
with digital consumption indications that
provide threewarning stages at 50%, 20%
and5%remaining capacitywith visual and
acoustic warnings. It also comes standard
with an automatic motion sensor and
alarm, in addition to a manually activated
emergency alarm," she concludes.
The MSA AirElite 4h has an opera-
tional temperature tolerance ranging from
minus 15 °C to 60 °C, and provides
breathing resistance at 30 ℓ/min at minus
3 mbar during inhalation, and 5 mbar
during exhalation. It is stored in a poly-
carbonate, self-extinguishing, impact-
resistant housing with antistatic coating,
and has standard casing dimensions of
600 mm x 360 mm x 190 mm and a total
weight of 15 kg.
●
Respiratory products manager, Suraksha Mohun.
• The extended workability time
of high performance concrete
with a low water/cement ratio
and therefore high durability
properties can also be set with
Sika ViscoFlow.
• Under different environmental
circumstances such as hot
temperatures, the required
workability time can be
achieved with Sika ViscoFlow.
●
bag, and from there through the inhalation
hose to the full face mask."
Safety matching economy
By making use of the TR conversion kit, Mo-
hun points out that a unit for real life opera-
tion canbe quickly and easily converted into a
training unit. "All of the training exercises can
then be performed at practically no cost with
a reusable training canister.The integrated P3
particle filter permits training under realistic
conditions inmist and non-toxic smoke.With
P3 particle filters, training under realistic
conditions in high dust environments, mist
and non-toxic smoke is possible."
Mohun explains that the MSA AirElite
4h does not require any additional logistics
such as expensive testing equipment, oxy-
gen transfer pumps or deep freezers. "This
reduces the investment and maintenance
costs of the AirElite 4h to a minimum. The
service time is entirely dependent on con-
sumption and, with an average breathing rate
of 30 ℓ/min, the expected time is between
four and six hours," she adds.
Approved safety
Mohun stresses that MSA places the safety
superplasticisers are adapted to local conditions in every country
and are thereby always based on proven SikaViscoCreteTechnology.
Consistent and rigorous further development has generated ex-
tremely robust PCEs for daily use, which are provided globally under
the Sika ViscoFlow brand name.
Sika ViscoFlow represents a valuable addition to Sika’s polymer
toolbox, broadening the range of applications and fulfilling chal-
lenging customer requirements.
• Sika ViscoFlow can be used for high performance slump
retention in any concrete facilitating an ensured target. This
stabilising effect can be achieved without any additional
retardation of the initial setting.
